NULL pointer dereference in Linux

CVE-2022-48884

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix command stats access after free Command may fail while driver is reloading and can't accept FW commands till command interface is reinitialized. Such command failure is being logged to command stats. This results in NULL pointer access as command stats structure is being freed and reallocated during mlx5 devlink reload (see kernel log below). Fix it by making command stats statically allocated on driver probe. Kernel log: [ 2394.808802] BUG: unable to handle kernel paging request at 000000000002a9c0 [ 2394.810610] PGD 0 P4D 0 [ 2394.811811] Oops: 0002 [#1] SMP NOPTI ... [ 2394.815482] RIP: 0010:native_queued_spin_lock_slowpath+0x183/0x1d0 ... [ 2394.829505] Call Trace: [ 2394.830667] _raw_spin_lock_irq+0x23/0x26 [ 2394.831858] cmd_status_err+0x55/0x110 [mlx5_core] [ 2394.833020] mlx5_access_reg+0xe7/0x150 [mlx5_core] [ 2394.834175] mlx5_query_port_ptys+0x78/0xa0 [mlx5_core] [ 2394.835337] mlx5e_ethtool_get_link_ksettings+0x74/0x590 [mlx5_core] [ 2394.836454] ? kmem_cache_alloc_trace+0x140/0x1c0 [ 2394.837562] __rh_call_get_link_ksettings+0x33/0x100 [ 2394.838663] ? __rtnl_unlock+0x25/0x50 [ 2394.839755] __ethtool_get_link_ksettings+0x72/0x150 [ 2394.840862] duplex_show+0x6e/0xc0 [ 2394.841963] dev_attr_show+0x1c/0x40 [ 2394.843048] sysfs_kf_seq_show+0x9b/0x100 [ 2394.844123] seq_read+0x153/0x410 [ 2394.845187] vfs_read+0x91/0x140 [ 2394.846226] ksys_read+0x4f/0xb0 [ 2394.847234] do_syscall_64+0x5b/0x1a0 [ 2394.848228] entry_SYSCALL_64_after_hwframe+0x65/0xca

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.002 (9.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 9.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2022-48884: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

  • Linux — versions 34f46ae0d4b38e83cfb26fb6f06b5b5efea47fdc, 5.18, 0
  • Linux Kernel — versions 6.2

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2022-48884?
CVE-2022-48884 is a medium-severity vulnerability in Linux, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2024-08-21.
How severe is CVE-2022-48884?
Medium severity. CVSS v3 base score is 5.5 out of 10.